The invention relates to a level transmitter, having a lever arm carrying a float, a support made of synthetic material, a bearing arranged on the support for the lever arm, a level sensor arranged on the support and comprising a cover and a substrate, a resistor network arranged on this substrate and associated with a contact structure, with the electrical connection of the contact structure generating, with the resistor network and as a function of the pivotal position of a lever arm, an electrical signal indicating the level, and having at least one permanent magnet for actuating the contact structure. Level transmitters are often used in fuel tanks together with feeding devices.
Level transmitters of the type mentioned at the outset have long been part of the prior art and are thus known. Because of increasing safety requirements, level transmitters in fuel tanks also have increasingly to be protected from excessively high electrostatic charges. Electrostatic charges in a lever-type transmitter may occur at the lever arm, as a result of moving through the fuel. Because the support and, if present, the bearing of the lever arm are made of synthetic material, the charges of the lever arm cannot be led away. In closed systems, there is no electrically conductive connection between the lever arm and the resistor network, or the grounding line leading to the resistor network, which could be used to discharge electrostatic charges.
It is the object of the invention to provide a level transmitter which is sufficiently protected from electrostatic charges. Protection from electrostatic charges should in this case be provided as inexpensively as possible.